Improvement in steam-engines



PATENT OFFICE.

JOHN ERICSSON, OF NEW YORK, N. Y.

IMPROVEMENT YIN STE'AlVI-ENGINES.

Specification forming part of Letters Patent No` 4l,6l2, dated February 16, 1864. l

To all whom it may concern:

Be it known that I, JOHN ERIcssoN, of the city, county, and State of New York, have invented a new and useful Improvement in Steam and other Engines; and I do hereby declare that the following is afull, clear, and eX- act description of the same, reference being had to the accompanying drawings, forming part of this specification, in which- Figure 1 is a vertical longitudinal section of a horizontal steam-engine having niyinvention applied. Fig. 2 is a plan of the same.

Similar letters of reference indicate corresponding parts in the two figures.

In all reciprocating steam-engines heretofore constructed the movement of the piston has produced a concussion or shaking of the bed or foundation upon which the engine has been supported, and a tendency to tear the engine away from said bed or foundation in many cases, to the great detriment of the structure in which the engine is contained. This action has been especially injurious in the case of horizontal engines arranged transversely to the keels of vessels for driving screw-propellers, and has been the great obstacle to the running of such engines at sufficiently high speeds to drive the propeller without the intervention of gearing or its equivalent .between the crank-shaft; and propellershaft. In such engines the weight of the piston and its attached piston-rods and crosshead is frequently many thousand pounds, and the inertia of this mass in the starting of the piston-reacts against one end of the cylinder and tends to move the cylinder and bed of the engine toward one side of the vessel, and the force required toarrest the piston as it completes its stroke,after having acquired a great momentum, reacts upon the framing and bed of the engine in the opposite direction to the reaction first mentioned, and tends to move the bed of the engine toward the other side of the vessel. In this way two distinct concussions are produced upon the vessel in a lateral direction during every stroke of the engine, or in every stroke of each piston, when more than one engine or an engine with more than one cylinder is used.

The object of this invention is to counteract the above-mentioned effect or tendency of the movements of the piston of an engine;

and to this end it consists in the connection with such piston of a weight which has a corresponding reciprocating motion, but always moves in an opposite direction to the piston, such weight being equal or nearly equal to the weight of the piston, its rod or rods and their connectitns with the crank, and moving the same distance, or being heavier and moving a correspondently less distance, or lighter and moving a correspondently greater distance.

To enable others skilled in the art to apply my invention to use, I will proceed to describe it with reference to the drawings.

A is the bed-plate; B, the cylinder; C, the piston; D D, the piston-rods; E, the crosshead; I I, the guides; F, the connecting-rod; G, the crank, and H the crankshaft. These parts are represented as arranged in the manner common to horizontal direct-action engines; but this particular arrangement is not essential to the success of my invention.

J is a lever, which is fast upon a rock-shaft, K, which is arranged parallel with the crankshaft H, in suitable bearings, a a, secured to bed-plate. The upper arm of this lever is connected by a rod, L, with a cross-head, E, and its lower arm, which passes through an opening in the bed-plate, is connected by a rod, M, with the weight N, which constitutes my invention, the said weight consisting of a solid mass of iron, or a box loaded in any suitable manner, and having attached to it and being supported on a pair of rollers, P P, which are arranged to run on a suitable horizontal track or plane surface, S, below the bedplate. The upper. and lower arms o'f the 1ever J, to which the piston and the weight N are respectively attached, are represented of equal length, and consequently-the weight N and its ,rod M should equal the weight of the piston, its rods, cross-head, and connectingrod.

It will be .understood that by the above-described system of connections with the piston the weight N will be caused to have a reciprocating movement corresponding with that of the piston, but will always move in an opposite direction, commencing and terminating its movement in either direction as the piston commences and terminates its movement in the opposite direction, and hence the reaction of theinertia ofthe piston at starting is counteracted and neutralized by the corresponding reaction of the inertia of the weight N, andthe reaction of the force required to check the momentum of the piston as it approaches the end of its stroke is counteracted and neutralized bythe corresponding reaction ofthe force required to check the momentum of the weight N. and the consequence is that the bed or foundation of the engine and the vessel or other structure which contains it are not subject to any perceptible concussion or shaking.

The mode of applying the weight N may be varied to suit circumstances, provided, always, that its reciprocating movement is always in the opposite direction to that of the piston.

There is shown in Fig. l in red linesamode of application by which the weight is brought nearly in line with the piston. The weightin this case is carried by one arm, b, of an elbowlever, which works on a fixed fulcrum, c, and the other arm, d, of which is connected by a rod, f, with the lower arm7 J', oi' the lever which isl fastk on the rock-shaft K.

In what is now known as the monitor en'- gine,77 which is the subject of my Letters Patent No. 20,782, the weight may be applied by simply adding an arm to the rock-shaft with which each piston is connected and securing the weight to such arm, the arrangement of which requires to bje such that the weight shall move as nearly as possible in a line parallel with the motion of the piston, and shall always move in the opposite direction to the piston.

The weight N, instead of being equal to the weight of i-he piston and its connections, and moving through the same distance7 may be less and so applied as to move through a correspondently-greater distance, or it may be greater and applied to move through a correspondentl y less distance. For instance, if the weight be only half the yweight of the piston and its connections, it should move twice the distance, and if double the weight of the piston and connections should move but half the distance. t'

/Vhat I claim as my' invention, and desire to secure by` Letters Patent, is-

Tlie employment of a reciprocating weight so connected with the piston of a steam or other engine as to movie always in the opposite direction to the motion of-the piston, and so proportioned as toloperate substantially as herein specified.

J. ERICSSON. Witnesses:

M. M. LIVINGSTON, SAMUEL W. TAYLoR. 

